JPH046550A - Silver halide photographic material - Google Patents

Abstract

PURPOSE:To enlarge a tone reproduction range, to stabilize the photographic material from the production of emulsion of the end of coating, and to enhance storage stability by forming a silver halide emulsion layer composed of specified 2 components. CONSTITUTION:The silver halide emulsion layer is composed of the 2 components of A and B, and A is a silver halide emulsion composed of plural components different in the amount of dye adsorbed per unit surface area of silver halide and spectrally sensitized by the sensitizing dye represented by formula I, and B is a silver halide emulsion not spectrally sensitized or if sensitized, having a spectral sensitivity maximum in a wavelength region shorter than that of the A. In formula I, each of R1 and R2 is alkyl or the like; each of L, L1, and L2 is CH or the like; Z1 is an atomic group necessary to form a benzoxazole or naphthoxazole ring; Z2 is an atomic group necessary to form an N-containing hetero ring; X<-> is an anion; (l) is 1 or 2; (m) is 0 or 1; and (n) is 0, 1, or 2, thus permitting the obtained photographic material to be good in the tone reproduction performance of filter characteristics and stable from the production of the emulsion to the end of coating and superior in storage stability after the production.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention particularly relates to a so-called multi-gradation photographic material in which various tones of different tones can be created using a filter.

(Prior Art) In general, black and white photographic papers are manufactured and sold separately in different gradations from No. 1 to No. 5, depending on the gradation of the negative to be printed by contact or enlargement. However, from the user's point of view, it was inconvenient that it was necessary to stock up infrequently used numbers of photographic paper in the i.

As a means to solve these problems, so-called sub-exposure type multi-gradation photographic paper, in which the gradation can be changed by applying sub-exposure before and after the main exposure, has been proposed and put into practical use. However, this method has the disadvantage that it is difficult to obtain a desirable change in gradation, and that a satisfactory finish of the photographic paper cannot be obtained. On the other hand, as a more superior method, multi-gradation photographic paper is known, in which various tones can be obtained by changing filters using one type of photographic paper. However, in producing multi-tone photographic paper using this method, a mixture of spectrally sensitized silver halide and silver halide which has not been spectrally sensitized is coated in the sensitized region, so the emulsion is manufactured. Desorption or exchange adsorption of the sensitizing dye occurs between the time of coating and the time of coating, impairing good gradation reproducibility.

As a technique to improve this point, Japanese Patent Application Laid-Open No. 62-215943
It has been proposed to use specific sensitizing dyes.

Furthermore, even if spectrally sensitized, the filter characteristics are created by the composite characteristics of the spectrally sensitized silver halide and the non-spectrally sensitized silver halide, so it is possible to obtain the highest contrast. The characteristic No. 5 tone is a characteristic of silver halide that has not been spectrally sensitized, and the closer it gets to No. 0 tone, the more the characteristics are affected by spectral sensitization, and all characteristic curves are linear and tone reproducible. It is desirable to have the following.

However, in the prior art dye sensitization method in which the amount of dye per unit surface area of silver halide is constant, the filter characteristic curve is truncated or curved, and is not linear, resulting in a significant decrease in tone reproducibility. This is because the dye sensitization characteristics do not have the sensitivity and tone that match the filter characteristics.
No matter what dye or emulsion is used, there is a need for a method that can freely create sensitivity and tone that match the filter characteristics.

(Object of the Invention) The object of the present invention is to provide multi-tone photographic paper with halogenated paper that has wide tone reproducibility, is stable from the time of emulsion production to the end of coating, and has excellent storage stability after production. Our purpose is to provide silver photographic materials.

(Structure of the Invention) The above objects of the present invention can be achieved by a silver halide photographic material characterized by having a silver halide emulsion layer consisting of the following two components.

(A) A spectral sensitized product comprising a plurality of components that are spectrally sensitized with a sensitizing dye represented by the following general formula (I) and are made to have different amounts of dye adsorption per unit surface area of silver halide. Silver halide emulsion.

β) A silver halide emulsion that is not spectrally sensitized or, even if it is, has a maximum spectral sensitivity at a wavelength shorter than that of the halide emulsion.

General formula (I) In the formula, R1 and R2 may be the same or different and each represents an alkyl group, an alkenyl group or an aryl group, L,
Ll and L2 each represent CM or CR3 (I'J is a lower alkyl group or aryl group), and Zl is a group necessary to form a benzoxazole ring having an aryl group or an aralkyl group at at least the 5th or/and 6th position. It is a group of atoms or represents a naphthoxazole ring. z2 represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle, X- represents an anion, t represents 1 or 2, m represents 0 or 1, and n represents 0.1 or 2.

The present invention will be described in more detail below.

A silver halide emulsion (A) spectrally sensitized with a sensitizing dye so as to have an absorption maximum in the range of 480 to 570 nm and consisting of a plurality of components having different amounts of dye adsorption per unit surface area of silver halide (hereinafter referred to as polyester). The preparation of a component color sensitized emulsion (component color sensitized emulsion) involves changing the ratio of the amount of silver halide emulsion to the amount of sensitizing dye, instead of having a fixed amount of silver halide dye adsorption (hereinafter referred to as "component color sensitized emulsion") in the conventional technology. By creating characteristics with different sensitivity and density based on the components, and finally using the composite characteristic curve, dye sensitization characteristics that match the filter characteristics are obtained.

In the multi-component color sensitized emulsion of the present invention, the dye-sensitized silver halide emulsion (8) may be arbitrarily divided according to the dye-sensitizing properties, preferably divided into 2=4 components. Dye sensitization is a process in which the ratio of the amount of silver halide emulsion and the amount of sensitizing dye is changed depending on the divided silver halide emulsion, and dye sensitization characteristics are formed by composite characteristics, and the number of divided silver halide emulsions is increased. As the amount of silver halide emulsion increases, the characteristic curve becomes smoother, and the movement of dye sensitizing characteristics is such that when a certain amount of sensitizing dye is added, when the amount of silver halide emulsion is small, it becomes high sensitivity, soft tone, and low density characteristics, and when it is large, it becomes low sensitivity, high contrast, and This takes advantage of the property of high concentration.

When creating a dye sensitization characteristic curve, the ratio of the amount of sensitizing dye to the amount of silver halide is increased to form toe characteristics using high sensitivity, soft tone, and low density characteristics.

In this case, the amount of silver halide used is preferably 30% or less of the silver halide emulsion. For the abdomen and shoulder of the dye-sensitizing characteristics, use low sensitivity, high tone, and high density characteristics while reducing the ratio of the amount of sensitizing dye to the amount of silver halide, and use the shoulder characteristics of each dye-sensitizing characteristic. Create a characteristic curve. By creating such a method, the characteristics at any concentration of the characteristic curve can be freely adjusted. Further, if necessary, sensitizing dyes may be used in combination.

The dye sensitization method for dividing silver halide may be carried out by sensitizing each dye and mixing the dyes, or by sequentially adding a silver halide emulsion and a sensitizing dye. Further, it is preferable to carry out dye ripening in order to increase the dye adsorption efficiency.

The mixing ratio of the silver halide emulsion N to which the dye of the present invention has been adsorbed and another silver halide emulsion (B) may be arbitrary, and preferably the ratio of emulsion (B) is from 2:1 to 1=3.

Furthermore, the I-Rhodan composition and particle size of the particles and β) may be the same or different. Furthermore, the method of adding a spectral sensitizer that sensitizes to wavelengths shorter than the wavelength maximum of (A) as required is (8) and (B).
) or after mixing (A) and (A), it is preferable that the wavelength maximum is 15 nm or more shorter than the other maximum wavelength.

The sensitizing dye in the region of 480 to 570 nm is a general formula (I) in which R+ and R2 may be the same or different and represent an alkyl group (for example, methyl, ethyl,
Lower alkyl groups such as propyl, butyl, pentyl, β-
Hydroxyalkyl groups such as hydroxyethyl, γ-hydroxypropyl, acyloxyalkyl groups such as β-acetoxyethyl, γ-acetoxypropyl, β-benzoyloxyethyl, β-methoxyethyl, β-ethoxyethyl, β-impropoxyethyl, Alkoxyalkyl groups such as β-(β-methoxyethoxy)ethyl, carboxyalkyl groups such as carboxymethyl, β-carboxyethyl, γ-carboxypropyl, alkoxycarbonyl groups such as methoxycarbonylmethyl, ethoxycarbonylmethyl, β-ethoxycarbonylethyl, etc. Alkyl group, β-
Sulfoalkyl groups such as sulfoethyl, γ-sulfopropyl, ε-sulfobutyl, aral-+ #L such as benzyl, 7-enethyl, nosulfoaralkyl groups such as sulfobenzyl, sulfophenethyl, etc.), alkenyl groups (e.g. allyl), aryl represents a group (eg phenyl).

L, Ll, and L2 each represent CH or CR3 (R3 is a lower alkyl group or an aryl group as described above for R1R2).

zl has an aryl group (e.g. phenyl) or an aralkyl group (e.g. benzyl,
7enethyl), or a group of atoms necessary to form a benzoxazole ring having a naphthoxazole ring (e.g., 7ethyl(2,1-d)oxazole, naph) [1,
2-d]oxazole, naphtho[2,3-d]oxazole, 8,9-dihydronaphtho[1,2-d]oxazole).

Z2 represents an atomic group necessary to complete a 5- or 6-membered nitrogen-containing heterocycle. The heterocycles are well known in cyanine dye chemistry, such as oxazoline ring, oxazole ring, benzoxazole ring, naphthoxazole ring, inoxazole ring, benzoinoxazole ring, oxazolopyridine ring, thiazoline ring, thiazole ring. ring, benzothiazole ring, naphthothiazole ring, thiazolopyridi/ring, thiazoloquinoline ring, 1,3.4-thiadiazole ring, selenazoline ring, selenazole ring, benzoselenazole ring, naphthoselenazole ring, pyridine ring,
Quinoline ring, benzo[f]quinoline ring, isoquinoline ring, acridine ring, imidazole ring, benzimidazole ring, naphthimidazole ring, indolenine ring, hengeindolenine ring, imidazoquinoxaline ring, 1,8-s7tyridine ring, There are pyrroline rings, etc. X- represents an acid anion (for example, methyl sulfate ion, ethyl sulfate ion, thiocyanate ion, toluenesulfonate ion, chloride ion, bromine ion, iodide ion, perchlorate ion, etc.), t is 1 or 2, m represents 0 or 1, and n represents 0 or 1 or 2.

Typical examples of dyes used in the present invention are listed below.
The present invention is not limited to this.

2H5 2H5 In the present invention, the sensitizing dye represented by the general formula (I) can be easily synthesized by a known method. For example, F, M, HomesM″The Cyanine
Dyes and Re1ated Compounds
'IntersciencePublisher,
New York (I964) and BE S EAR
CHDISCLO8URE vol, 176 pag
e 23 N term (RD-17643, Dec, 197
It can be carried out by the method described in the literature cited in 8).

The sensitizing dye used in the present invention is water or water-mixable (mi
It is added to the silver halide emulsion as a solution in an organic solvent such as methanol, ethanol, methyl cellosolve, etc., and after being adsorbed, a new silver halide emulsion can be mixed. It is also possible to dissolve it in a solvent that is insoluble in the pond water and add it to the emulsion in the form of a dispersion.

The amount of the sensitizing dye added in this case varies depending on the type of the sensitizing dye or the type of emulsion, but the optimum amount can usually be arbitrarily selected within the range of 3 to 5 ooq per mole of silver halide.

Any of button bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide and silver chloride may be used as silver halide in the photographic emulsion layer of the photographic material used in the present invention.

The preferred silver halide is silver iodochlorobromide containing up to 5 moles of silver iodide. Further, the grain size of the silver halide used is arbitrary, but preferably 0.8 μm or less.

These silver halide emulsions can be prepared by known methods such as an ammonia method, a neutral method, and an acid method. Further, crystal formation and growth can be performed by the conventionally well-known single jet method, multi-jet method, etc.

The emulsion according to the invention can contain various additives. For example, when chemically sensitizing with a gold compound, other chemical sensitizers (e.g., sulfur sensitizers such as thiourea and hypo, noble metal sensitizers other than total, and reduction sensitizers) are also used. be able to. Furthermore, a spectral sensitizer, a stabilizer, an anti-capri agent, a surfactant, a developer, a development accelerator, a hardening film, which sensitizes the silver halide spectrally sensitized with the general formula (I) to a wavelength shorter than the maximum wavelength. It may contain agents, hardening accelerators, couplers, desilvering accelerators, dye removal improvers, brighteners, thickeners, and the like.

Protective colloids for the silver halide emulsion used in the present invention include gelatin, modified gelatin, albumin, agar, gum arabic, natural products such as alginic acid, polyvinyl alcohol, polyvinylpyrrolidone, and copolymers of acrylamide, acrylic acid, and vinylimidazole. Water-soluble synthetic resins such as

The emulsions of this invention are coated onto a suitable support such as glass, cellulose acetate film, polyethylene terephthalate film, paper, baryta-coated paper, polyolefin (eg, polyethylene, polypropylene, etc.) coated paper. These supports may be corona treated by a known method, and may also be undercoated by a known method if necessary.

The silver halide photographic emulsion according to the present invention is coated with a protective layer, an intermediate layer, an ultraviolet absorbing layer, an undercoat layer or other silver halide emulsions, if necessary.

After exposure, the light-sensitive material prepared using the silver halide emulsion of the present invention can be developed by a commonly used known method. The black and white developer is an alkaline solution containing developing agents such as hydroxybenzenes, aminophenols, and aminobenzenes used in ordinary photography, as well as sulfites, carbonates, bisulfites, and other alkali metal salts.
It can include bromide, iodide, and the like.

The light-sensitive material of the present invention has good tone reproducibility of filter characteristics due to multi-component dye sensitization, and by using a specific cyanine dye, it is stable from the time of emulsion production to the first coating, and has excellent storage stability after production. The point is that

The present invention will be explained in more detail below with reference to Examples, but the present invention is of course not limited thereto.

Example 1 Chemically sensitized silver iodochlorobromide emulsion (0.4 molt silver iodide,
The emulsion was subjected to multi-component dye sensitization according to the present invention using a sensitizing dye (I3) with stable dye adsorption properties to silver bromide (60 molti, average grain size 0.35 μm), and the emulsion according to the prior art. A one-component color sensitized emulsion was prepared.

-The component color sensitized emulsion contains a sensitizing dye of 10η/silver 10? In addition, the emulsion was left at 50°C for 30 minutes to reach 40°C, and a corresponding amount of the same emulsion, which had not been dye-sensitized, was mixed with silver.

Multi-component color sensitized emulsions are prepared by mixing silver 101 to 2 parts before dye sensitization.
Divide 4:4 and similarly divide sensitizing dye 10 to 1.5:
4: Divide into 4.5 parts, add 1.5% of the divided sensitizing dye to 20% of the divided emulsion, leave for 10 minutes at 50°C, then add 40% of the divided emulsion, and divide when the temperature reaches 50°C. Add 40% of the sensitizing dye, leave to stand for 10 minutes, and add the final divided emulsion 4.
When the temperature reached 50°C, 4.5% of the remaining sensitizing dye was added and left for 10 minutes. The temperature was lowered to 40° C., and a corresponding amount of the same emulsion, which had not been dye-sensitized, was mixed with silver. After adding stabilizers, hardeners, and surfactants to both, they were divided into two equal parts, and one half was placed on photographic polyethylene laminated paper as silver.
It was applied so that the ratio was t/d. The other one is 38℃
After that, the coating was applied in the same manner.

These samples were processed using Kodak POLYCONTRAST.
After exposure through a wedge with a density difference of 0.15 to FILTER 8, a developer for photographic paper, Gencor (manufactured by Mitsubishi Paper Industries) was applied.
Developed for 90 seconds at 20°C using
, effective exposure range, and gamma, and table the obtained results.
and shown in Figure 1.

Table 1 As is clear from the above coating results, it can be seen that the multicomponent color sensitized emulsion is as stable as the single component color sensitized emulsion even after 12 hours of emulsion aging. Although there is almost no difference in numerical values between the present invention and those outside the present invention, as is clear from the filter characteristic curve in Figure 1, the multi-component color sensitized emulsion is linear;
It can be seen that the range of tone is expanding.

Example 2 Similar to Example 1, a relatively sharp sensitizing dye (2)
An emulsion was created using -Component color sensitized emulsion is Example 1
A multi-component color sensitized emulsion was prepared in the same manner as before, and before dye sensitization, silver 10f was divided into 1.5:2.5:3:3, and sensitizing dye 10■ was divided into 2:2:3:3. Example 1
Created in the same way.

The results obtained are shown in Table-■.

(Leaving space below) Table - ■ As is clear from the above coating, by using a sensitizing dye with good sharpness, single-component dye-sensitized emulsions have a narrow range of tone, while multi-component color-sensitized emulsions have a narrow range of tone. It can be seen that the difference and tone reproduction are expanding. By changing the ratio between the amount of silver halide and the amount of sensitizing dye in this way, the sensitizing dye factor can be completely excluded.

Example 3 In order to evaluate the storage stability of the freshly prepared sample used in Example 1, it was kept at 50°C, 80°C, and RH every 6 days, and then the sample before and after storage was heated with a concentration difference of 0.15. After exposure through a wedge, development was performed in the same manner as in Example 1, and sensitivity (relative value) and capri were measured.

The results obtained are shown in Table-■.

Table - ■

[Brief explanation of drawings]

FIG. 1 shows changes in characteristic curves of the present invention and conventional multi-tone photographic paper. As is clear from the results in Table ■, the storage stability when using the multi-component dye sensitization method of the present invention does not increase fog, increase sensitivity, or desensitize, and has excellent storage stability after production. I can see that there is. (Effects of the Invention) The multi-component dye sensitizing method and sensitizing dye of the present invention are stable from the time of manufacturing the emulsion to the end of coating, have excellent storage stability after manufacturing, and have excellent multi-component dye sensitization during tone reproduction. A silver halide photosensitive material for gradation can be provided. ~ ~ Procedural amendment (release) 1. Description of the case 1990 Patent Application No. 107942 2 Name of the invention Silver halide photographic material 3 Person making the amendment Patent Department Mitsubishi Paper Mills Co., Ltd. 4 Date of amendment order July 31, 1990 (Shipping mortar) ) 5゜Figure 1 of the "drawings" attached to the application subject to amendment

Claims (1)

[Scope of Claims] A silver halide photographic material characterized by having a silver halide emulsion layer consisting of the following two components (A) and (B). (A) A spectral sensitized product comprising a plurality of components that are spectrally sensitized with a sensitizing dye represented by the following general formula (I) and are made to have different amounts of dye adsorption per unit surface area of silver halide. Silver halide emulsion. (B) A silver halide emulsion that is not spectrally sensitized or, even if it is, has a maximum spectral sensitivity at a wavelength shorter than that of silver halide (A). General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. CH or CR_3(R
_3 is a lower alkyl group or aryl group), and Z_
1 is an atomic group necessary to form a benzoxazole ring having an aryl group or an aralkyl group at at least the 5 and/or 6 positions, or represents a naphthoxazole ring. Z_2 represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle, X^- is an anion, l is 1 or 2,
m represents 0 or 1, and n represents 0, 1 or 2. ]